Gas Alarm FAQ

Fire security design for garage, motor repair shop and parking area. Fire security alarm and explosion proof design for chemical factory, oil field etc.
Post Reply
Jim
Posts: 51
Joined: Sat Oct 31, 2020 1:01 pm

Gas Alarm FAQ

Post by Jim »

1. The meaning of %LEL concentration in the measurement range of gas alarm
%LEL refers to the lower limit of explosion. The lowest concentration of combustible gas that will explode when it encounters an open fire in a confined space. In the case of methane, the lower limit of explosion European standard: 100%LEL=4.4% VOL 1% LEL=440PPm.

2. The meaning of gas alarm measurement unit vol% concentration
VOL % is the volume percentage concentration, VOL is the volume ratio, is the volume ratio of non-flammable gas.
That is, the unit volume is divided into 100 parts, including 1 part of gas, whose concentration value is 1vol%. Therefore, the concentration of gas is commonly detected. For example, when the gas concentration is 100vol% in replacement, it indicates that the pipeline is pure gas, and we get that 1vol%=10000PPm

3. The meaning of measuring PPM concentration
It means a concentration of one part per million, which is divided into a million parts per unit volume. One part of the gas is 1PPm. Therefore, PPm is a very low concentration, which is used to measure whether there is a gas leak.
1PPm= 1/millionth concentration =1cm³in1m³, 1vol%=10000PPm

4. How is the pressure of gas pipeline converted
1Mpa=1000Kpa=1000000pa=10 kg, the general low pressure pipeline between 2000pa-3000pa.

Post Reply